TY - GEN AU - B M Levin C2 - , National Institute of Standards and Technology, Gaithersburg, MD DA - 1959-01-01 05:01:00 DO - https://doi.org/10.6028/NBS.TN.33 LA - en PB - , National Institute of Standards and Technology, Gaithersburg, MD PY - 1959 TI - Distribution of incoming lettermail at the Baltimore, Maryland city post office: ER -